I ran is why my GCP markers dont agree with the final surface height after processing. I checked the DEM against my original surveyed GCP points and have found discrepancies between 1 + 1.6 meters! I read another post that said to untick all image reference data and force AS to use the GCP values. If this is the case wouldn't that be the process every time?
It all depends on how accurate the position coordinates of the camera is. If you're talking a consumer drone, the positioning accuracy is terrible. It's suficient to allow the software to place the cameras position relative to the other cameras. But compared to accurately surveyed GCPs, there is no comparison. That's why you tell the software that the GCPs are precise, and the cameras need adjusting based upon them.
On the other hand, if you are using either a RTK or PPK workflow for your drone, the camera coordinates may be just as accurate as the GCPs. So, in that case, you would tell Metashape that the cameras are equally as accurate as the GCPs and MS builds the model accordingly.
Hopefully that makes sense.
Dave